Question

Smell of gas in 2000 Chevrolet Blazer

I have a 2000 Chevrolet Blazer, 6 cylinder with four wheel drive capability. There is a smell of gas in the vehicle. The gas gauge fluctuates erratically. The fuel pump in tank is not making any noise and seems to be providing fuel with no problems. I am wondering that there could be a gas leak and also a grounding problem with wiring to gas gauge I am also wondering how I can test gas gauge wiring to see if it is wired correctly or gas gauge in tank is defective. Also a wiring diagram and gas tank diagram would be helpful. The gas leak I know could be from top of tank or gas line from tank. The tank is plastic so I know there is no rotting of tank. Any ways that could be submitted on how to check for these problems would be helpful.